DEVELOPMENT AND APPLICATION OF MANAGEMENT FOR FOUR SHRIMP DISEASES (TSV, YHV, WSSV AND NHP) IN THE WHITE SHRIMP Penaeus vannamei THROUGH DIFFERENT STRATEGIES

Abstract

A series of studies were conducted as part of my dissertation research on certain diseases of farmed penaeid shrimp and on strategies that might be applied to manage these diseases. These studies focused on the development and application of management for four shrimp diseases (TSV, YHV, WSSV and NHP) in the white shrimp Penaeus vannamei through different strategies. The studies focused on efforts to identify a new strain of Taura syndrome virus (TSV), and the prevention or mitigation of infection by Yellow Head Disease (YHD), White Spot Disease (WSD), and Necrotizing Hepatopancreatitis (NHP). The new strain of TSV reported in this study is among the most pathogenic strains discovered to date. Disease management strategies investigated include the prevention of YHD in the Americas by pre-exposing Specific-Pathogen-Free (SPF) Penaeus vannamei to TSV. The other strategy investigated involved the use of a prototype "vaccine" that binds to the specific shrimp cell receptors and thus, prevents WSSV from establishing an infection. The last strategy attempted to elucidate the reasons for the very low prevalence of NHP in commercial shrimp ponds in Colombia. It was found that through establishment of a breeding program in which shrimp were selected for resistance to TSV infection, Colombian shrimp farmers also, but indirectly, selected for resistance to NHP.